Compare phones
| Global Score | |
| 91.8 | 90.7 |
| Basic Information | |
| Samsung | Samsung |
| Android 11 | Android 14 |
| 2021-01-29 | -- |
| 5.97 x 2.80 x 0.31 inches | -- |
| 6.03 ounces | -- |
| Gray, Phantom pink, Violet and White | -- |
| Aluminum and Plastic | Glass (Corning Gorilla Glass) and Titanium |
| Scratch-Resistant Glass | Scratch-Resistant Glass |
| $ 722.00 | -- |
| Display / Screen | |
| 6.2 inches | 6.8 inches |
| 2400 x 1080 pixels | 3088 x 1440 pixels |
| Dynamic AMOLED | Dynamic AMOLED |
| 424 pixels per inch | 501 pixels per inch |
| 1300 cd/m2 brightness | 2600 cd/m2 brightness |
| No touch screen | No touch screen |
| 9.2 | 10.2 |
| Performance | |
| Qualcomm Snapdragon 888 chipset | Qualcomm Snapdragon 8 Gen 4 chipset |
| Kryo 680, 64-bit, 5 nm (Octa-Core 2840 MHz) processor | processor |
| 8 GB RAM | 12 GB RAM |
| Adreno 660 GPU | Yes GPU |
| 9.63 | 6.21 |
| Storage | |
| 128 GB internal memory | 256 GB internal memory |
| No SD card slot | No SD card slot |
| 10.1 | 13.3 |
| Camera | |
| 12.00 MP + 10.00 MP | 200.00 MP + 12.00 MP |
| f/1.80 aperture | f/1.70 aperture |
| 26.00mm focal length | 24.00mm focal length |
| 0.57 inches (1/1.76") sensor | 0.77 inches (1/1.3") sensor |
| 7680 x 4320 (24 fps) video resolution | 7680 x 4320 (30 fps) video resolution |
| 1280 x 720 (960 fps) (HD) slow motion video | 1920 x 1080 (240 fps) (Full HD) slow motion video |
| 10.78 | 14.74 |
| Networks | |
| Wi-Fi | Wi-Fi |
| Mobile Hotspot | Mobile Hotspot |
| 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA | 5G, 5G, LTE-A (4G), LTE (4G), HSPA+ (4G) and HSDPA |
| Nano SIM | Nano SIM |
| 10.7 | 10.6 |
| Battery Life | |
| 4000mAh Li - Polymer Battery | 5000mAh Li - Ion Battery |
| Non-Removable Battery | Non-Removable Battery |
| Wireless Charging | Wireless Charging |
| 5.92 | 6.8 |
| Other Features | |
| Bluetooth 5.0 | Bluetooth 5.3 |
| GPS | GPS |
| NFC | NFC |
| Fingerprint ID Scanner | Fingerprint ID Scanner |
| Accelerometer, Barometer, Compass, Gyroscope, Light Sensor and Proximity Sensor | Accelerometer, Barometer, Compass, Gyroscope, Light Sensor and Proximity Sensor |
| FM Radio | -- |
Comparison review
Galaxy S21 has a general score of 91.8, which is a bit better than Galaxy S25 Ultra's global score of 90.7. Both of these phones work with Android operating system, but the Galaxy S21 has an older 11 version and Galaxy S25 Ultra has Android 14 version. Galaxy S21 has an extremely better processor than Galaxy S25 Ultra, although it has 4 GB less RAM, they both have the same number of cores.
The Galaxy S25 Ultra counts with a sharper screen than Galaxy S21, because it has a quite larger screen, way more brightness, a quite higher number of pixels per inch in the screen and a higher 1440 x 3088px resolution. The Samsung Galaxy S25 Ultra captures greater pictures and videos than Samsung Galaxy S21, and although they both have the same video resolution, the Samsung Galaxy S25 Ultra also has a larger aperture to take better images and videos in low light environments, a camera in the back with a way better resolution, faster video frame rate and a lot larger sensor taking way better quality pictures.
The Samsung Galaxy S25 Ultra has a very superior memory capacity to install games and applications than Galaxy S21, because it has 256 GB internal storage capacity. The Samsung Galaxy S25 Ultra counts with longer battery life than Samsung Galaxy S21, because it has 5000mAh of battery capacity.
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